1) x^2 - x - 56 = 0(x - 8)(x + 7) = 0x = 8 or x = -7
2) -x^2 + x + 72 = 0-(x - 9)(x + 8) = 0x = 9 or x = -8
3) x^2 + x - 90 = 0(x + 10)(x - 9) = 0x = -10 or x = 9
4) x^2 + x - 210 = 0(x - 14)(x + 15) = 0x = 14 or x = -15
Корни уравнений:1) x = 8, x = -72) x = 9, x = -83) x = -10, x = 94) x = 14, x = -15
1) x^2 - x - 56 = 0
(x - 8)(x + 7) = 0
x = 8 or x = -7
2) -x^2 + x + 72 = 0
-(x - 9)(x + 8) = 0
x = 9 or x = -8
3) x^2 + x - 90 = 0
(x + 10)(x - 9) = 0
x = -10 or x = 9
4) x^2 + x - 210 = 0
(x - 14)(x + 15) = 0
x = 14 or x = -15
Корни уравнений:
1) x = 8, x = -7
2) x = 9, x = -8
3) x = -10, x = 9
4) x = 14, x = -15